D2 is a D-type tool steel alloy. D-type steels typically contain between 10 and 13 percent chromium. D2 steel is air-hardened and retains its strength up to a temperature of 425 degrees Celsius with minimal distortion.
Because of its high resistance to heat and pressure, D2 steel is ideal for use with long work applications requiring high wear resistance and high compression strength. Common uses for D2 steel include drawing and forging dies and casting die blocks, machine parts, seaming rolls, shear blades and tire shredders. Certain D-type steels are considered stainless or semi-stainless due to their high chromium content.